IMPLICATIONS OF WATER-ROCK REACTIONS IN LAVA TUBE ENVIRONMENTS AT LAVA BEDS NATIONAL MONUMENT

Author

Jessica Peluso, University of Rhode IslandFollow

Date of Award

2024

Degree Type

Thesis

Degree Name

Master of Science in Biological and Environmental Sciences (MSBES)

Specialization

Environmental and Earth Sciences

Department

Geosciences

First Advisor

Dawn Cardace

Abstract

Lava caves are widespread in volcanic terrains on Earth and other worlds, containing metal-rich rock compositions that attract life and react with waters in dark and secluded environments. Water-rock reactions in these settings promote alteration of the basalt substrate and initiate the formation of secondary minerals in addition to colonization by microbes. The varieties of secondary minerals present in lava caves can serve as indicators of weathering types, previous environmental conditions, reaction progress, and may even be useful in preserving potential biosignatures. Secondary mineral samples from lava caves at Lava Beds National Monument were collected and analyzed with X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) to determine their mineralogy. Geochemical modeling of similar basalt and groundwater interactions, using the Geochemist’s Workbench, was conducted to compare with field-based findings. Carbonate and clay minerals were abundant amongst samples collected in the field and were predicted in model outputs in the initial stages of the reaction. This indicates water-rock reactions at Lava Beds National Monument are still ongoing, have yet to reach thermodynamic equilibrium, and may provide energy to microbes living within the caves. Since lava caves are present on other worlds and are sheltered from environmental stresses through time, they are ideal astrobiological targets where minerals, microbes or biosignatures may be found.

Recommended Citation

Peluso, Jessica, "IMPLICATIONS OF WATER-ROCK REACTIONS IN LAVA TUBE ENVIRONMENTS AT LAVA BEDS NATIONAL MONUMENT" (2024). Open Access Master's Theses. Paper 2467.
https://digitalcommons.uri.edu/theses/2467